org.graalvm.compiler.nodes.util

Class ConstantReflectionUtil

java.lang.Object

org.graalvm.compiler.nodes.util.ConstantReflectionUtil

public final class ConstantReflectionUtil
extends Object

Helper functions to access complex objects on the application heap via the ConstantReflectionProvider.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ConstantReflectionUtil.ArrayBaseOffsetProvider

Method Summary

Modifier and Type	Method and Description
static boolean	canFoldReads(CanonicalizerTool tool, ValueNode array, ValueNode offset, JavaKind stride, int len, ConstantReflectionUtil.ArrayBaseOffsetProvider arrayBaseOffsetProvider) Return true if the array and the starting offset are constants, and we can perform len in-bounds constant reads starting at byte offset offset.
static byte[]	loadByteArrayConstant(ConstantReflectionProvider crp, JavaConstant targetArg, int maxLength)
static char[]	loadCharArrayConstant(ConstantReflectionProvider crp, JavaConstant targetArg, int maxLength)
static int[]	loadIntArrayConstant(ConstantReflectionProvider crp, JavaConstant targetArg, int maxLength)
static int	readTypePunned(ConstantReflectionProvider provider, JavaConstant array, JavaKind arrayKind, JavaKind stride, int index) Reads and zero extends 1, 2 or 4 bytes from a constant byte[], char[] or int[] array.
static Integer	startIndex(CanonicalizerTool tool, ValueNode array, JavaConstant offset, JavaKind stride, ConstantReflectionUtil.ArrayBaseOffsetProvider arrayBaseOffsetProvider) Compute an element index from a byte offset from the start of the array object.

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

loadByteArrayConstant

public static byte[] loadByteArrayConstant(ConstantReflectionProvider crp,
                                           JavaConstant targetArg,
                                           int maxLength)

loadCharArrayConstant

public static char[] loadCharArrayConstant(ConstantReflectionProvider crp,
                                           JavaConstant targetArg,
                                           int maxLength)

loadIntArrayConstant

public static int[] loadIntArrayConstant(ConstantReflectionProvider crp,
                                         JavaConstant targetArg,
                                         int maxLength)

readTypePunned

public static int readTypePunned(ConstantReflectionProvider provider,
                                 JavaConstant array,
                                 JavaKind arrayKind,
                                 JavaKind stride,
                                 int index)

Reads and zero extends 1, 2 or 4 bytes from a constant byte[], char[] or int[] array.

Parameters:

array - a constant java byte[], char[] or int[] array.

arrayKind - the array's element kind (JavaKind.Byte for byte[], JavaKind.Char for char[] and JavaKind.Int for int[]).

stride - the element width to read from the array (JavaKind.Byte == 1 byte, JavaKind.Char == 2 bytes and JavaKind.Int == 4 bytes). The stride must not be smaller than the array element kind, e.g. reading a byte from an int[] array is not supported.

index - the index to read from, scaled to stride.

Returns:

the bytes read, zero-extended to an int value.

canFoldReads

public static boolean canFoldReads(CanonicalizerTool tool,
                                   ValueNode array,
                                   ValueNode offset,
                                   JavaKind stride,
                                   int len,
                                   ConstantReflectionUtil.ArrayBaseOffsetProvider arrayBaseOffsetProvider)

Return true if the array and the starting offset are constants, and we can perform len in-bounds constant reads starting at byte offset offset. Return false if not everything constant or if we would try to read out of bounds.

startIndex

public static Integer startIndex(CanonicalizerTool tool,
                                 ValueNode array,
                                 JavaConstant offset,
                                 JavaKind stride,
                                 ConstantReflectionUtil.ArrayBaseOffsetProvider arrayBaseOffsetProvider)

Compute an element index from a byte offset from the start of the array object. Returns null if the given offset is not aligned correctly for the element kind's stride.